ncr810lib.c

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*
* ncr810ThreadAbort - abort a thread
*
* If the thread is not currently connected, do nothing and return FALSE to
* indicate that the SCSI manager should abort the thread.
*
* Otherwise (the thread is active onthe controller), build an ABORT or
* ABORT TAG message which will (eventually) be sent, causing the taget to
* disconnect.  Abort the current script run so that this message can be
* sent.  Set the state of the thread accordingly, and return TRUE to
* indicate that the controller driver will handle the abort process.
*
* RETURNS: TRUE if the thread is being aborted by this driver (i.e. it is
* currently active on the controller, else FALSE.
*
* NOMANUAL
*/
LOCAL BOOL ncr810ThreadAbort
    (
    SIOP *          pSiop,		/* ptr to controller info */
    NCR810_THREAD * pThread		/* ptr to thread info     */
    )
    {
    BOOL          tagged;
    SCSI_CTRL *   pScsiCtrl   = (SCSI_CTRL *)   pSiop;
    SCSI_THREAD * pScsiThread = (SCSI_THREAD *) pThread;

    SCSI_DEBUG_MSG ("ncr810ThreadAbort: thread 0x%08x (state = %d) aborting\n",
		    (int) pThread, pScsiThread->state, 0, 0, 0, 0);

    if (pScsiThread != pScsiCtrl->pThread)
	return (FALSE);
    
    switch (pScsiThread->state)
	{
	case SCSI_THREAD_INACTIVE:
	case SCSI_THREAD_WAITING:
	case SCSI_THREAD_DISCONNECTED:
	    return (FALSE);
	    break;

	default:
	    /*
	     *	Build an ABORT (or ABORT TAG) message.  When this has been
	     *	sent, the target should disconnect.  Mark the thread aborted
	     *	and continue until disconnection.
	     */
	    tagged = (pScsiThread->tagNumber != NONE);

	    pScsiCtrl->msgOutBuf[0] = tagged ? SCSI_MSG_ABORT_TAG
		    	    	    	     : SCSI_MSG_ABORT;
	    pScsiCtrl->msgOutLength = 1;
	    pScsiCtrl->msgOutState  = SCSI_MSG_OUT_PENDING;

	    ncr810Abort (pSiop);
	    
    	    ncr810ThreadStateSet (pThread, SCSI_THREAD_ABORTING);
	    break;
	}

    return (TRUE);
    }


/*******************************************************************************
*
* ncr810Event - NCR 53C810 SCSI controller event processing routine
*
* Parse the event type and act accordingly.  Controller-level events are
* handled within this function, and the event is then passed to the current
* thread (if any) for thread-level processing.
*
* Note the special case when (re)selection occurs: if there is a current
* thread when the event occurs, it receives the event (and is assumed to
* defer itself) before the identification thread is made current.  The
* event is then forwarded to the identification thread.
*
* RETURNS: N/A
*/
LOCAL void ncr810Event
    (
    SIOP *         pSiop,
    NCR810_EVENT * pEvent
    )
    {
    SCSI_CTRL  *    pScsiCtrl  = (SCSI_CTRL *)  pSiop;
    SCSI_EVENT *    pScsiEvent = (SCSI_EVENT *) pEvent;
    NCR810_THREAD * pThread    = (NCR810_THREAD *) pScsiCtrl->pThread;
    
    SCSI_DEBUG_MSG ("ncr810Event: received event %d (thread = 0x%08x)\n",
		    pScsiEvent->type, (int) pThread, 0, 0, 0, 0);

    /*
     *	Do controller-level event processing
     */
    switch (pScsiEvent->type)
	{
	case NCR810_SELECTED:
	case NCR810_RESELECTED:
	    /*
	     *	Forward event to current thread, if any (it should defer)
	     *	then install a reserved thread for identification purposes.
	     */
    	    if (pThread != 0)
	    	ncr810ThreadEvent (pThread, pEvent);

    	    pScsiCtrl->peerBusId = pScsiEvent->busId;

    	    pScsiCtrl->pThread = pScsiCtrl->pIdentThread;
	    
	    pScsiCtrl->pThread->role = (pScsiEvent->type == NCR810_SELECTED)
		    	    	     ? SCSI_ROLE_IDENT_TARG
				     : SCSI_ROLE_IDENT_INIT;

	    pThread = (NCR810_THREAD *) pScsiCtrl->pThread;

	    scsiMgrCtrlEvent (pScsiCtrl, SCSI_EVENT_CONNECTED);
	    break;

	case NCR810_DISCONNECTED:
	case NCR810_CMD_COMPLETE:
	case NCR810_UNEXPECTED_DISCON:
	case NCR810_SCSI_TIMEOUT:
    	    pScsiCtrl->peerBusId = NONE;
    	    pScsiCtrl->pThread   = 0;

	    scsiMgrCtrlEvent (pScsiCtrl, SCSI_EVENT_DISCONNECTED);
	    
	    break;

	case NCR810_SCSI_BUS_RESET:
    	    pScsiCtrl->peerBusId = NONE;
    	    pScsiCtrl->pThread   = 0;

    	    scsiMgrBusReset (pScsiCtrl);
	    break;

	default:
	    /*
	     *	Any other event type is assumed to be thread-specific.
	     *	The thread event handler will report an error if it's
	     *	not a valid type.
	     */
	    if (pThread == 0)
		{
	    	logMsg ("ncr810Event: invalid event type (%d)\n",
		    	pScsiEvent->type, 0, 0, 0, 0, 0);
		}
	    break;
	}
    /*
     *	If there's a thread on the controller, forward the event to it
     */
    if (pThread != 0)
	ncr810ThreadEvent (pThread, pEvent);
    }

    
/*******************************************************************************
*
* ncr810ThreadEvent - NCR 53C810 thread event processing routine
*
* Forward the event to the proper handler for the thread's current role.
*
* If the thread is still active, update the thread context (including
* shared memory area) and resume the thread.
*
* RETURNS: N/A
*
* NOMANUAL
*/
LOCAL void ncr810ThreadEvent
    (
    NCR810_THREAD * pThread,
    NCR810_EVENT *  pEvent
    )
    {
    SCSI_EVENT *  pScsiEvent  = (SCSI_EVENT *)  pEvent;
    SCSI_THREAD * pScsiThread = (SCSI_THREAD *) pThread;
    SIOP *        pSiop       = (SIOP *)        pScsiThread->pScsiCtrl;
    NCR810_SCRIPT_ENTRY entryPt;
    
    SCSI_DEBUG_MSG ("ncr810ThreadEvent: thread 0x%08x: received event %d\n",
		    (int) pThread, pScsiEvent->type, 0, 0, 0, 0);

    switch (pScsiThread->role)
	{
	case SCSI_ROLE_INITIATOR:
	    ncr810InitEvent (pThread, pEvent);

	    entryPt = NCR810_SCRIPT_INIT_CONTINUE;
	    break;
	    
	case SCSI_ROLE_IDENT_INIT:
	    ncr810InitIdentEvent (pThread, pEvent);

	    entryPt = NCR810_SCRIPT_INIT_CONTINUE;
	    break;

	case SCSI_ROLE_IDENT_TARG:
	    ncr810TargIdentEvent (pThread, pEvent);

	    entryPt = NCR810_SCRIPT_TGT_DISCONNECT;
	    break;
	    
	case SCSI_ROLE_TARGET:
	default:
	    logMsg ("ncr810ThreadEvent: thread 0x%08x: invalid role (%d)\n",
		    (int) pThread, pScsiThread->role, 0, 0, 0, 0);
	    entryPt = NCR810_SCRIPT_TGT_DISCONNECT;
	    break;
	}

    /*
     *	Resume thread iff it is still connected
     */
    switch (pScsiThread->state)
	{
	case SCSI_THREAD_INACTIVE:
	case SCSI_THREAD_WAITING:
	case SCSI_THREAD_DISCONNECTED:
	    break;

	default:
    	    ncr810ThreadUpdate (pThread);

	    if (ncr810Resume (pSiop, pThread, entryPt) != OK)
	    	{
	    	SCSI_ERROR_MSG ("ncr810ThreadEvent: failed to resume thread\n",
			    	0, 0, 0, 0, 0, 0);
	
		ncr810ThreadFail (pThread, S_scsiLib_DISCONNECTED);
	    	}
	    break;
	}
    }


/*******************************************************************************
*
* ncr810InitEvent - NCR 53C810 initiator thread event processing routine
*
* Parse the event type and handle it accordingly.  This may result in state
* changes for the thread, state variables being updated, etc.
*
* RETURNS: N/A
*
* NOMANUAL
*/
LOCAL void ncr810InitEvent
    (
    NCR810_THREAD * pThread,
    NCR810_EVENT *  pEvent
    )
    {
    SCSI_EVENT *  pScsiEvent  = (SCSI_EVENT *)  pEvent;
    SCSI_THREAD * pScsiThread = (SCSI_THREAD *) pThread;
    SCSI_CTRL *   pScsiCtrl   = pScsiThread->pScsiCtrl;

    /*
     *  Update controller msg in/out state after script completes
     */
    pScsiCtrl->msgOutState = pThread->nMsgOutState;
    pScsiCtrl->msgInState  = pThread->nMsgInState;
    
    /*
     *	Parse script exit status; handle as necessary
     */
    switch (pScsiEvent->type)
	{
	case NCR810_DISCONNECTED:
    	    SCSI_DEBUG_MSG ("DISCONNECT message in\n", 0, 0, 0, 0, 0, 0);

	    scsiMgrThreadEvent (pScsiThread, SCSI_THREAD_EVENT_DISCONNECTED);

	    ncr810ThreadStateSet (pThread, SCSI_THREAD_DISCONNECTED);
	    break;

	case NCR810_CMD_COMPLETE:
	    SCSI_DEBUG_MSG ("COMMAND COMPLETE message in\n", 0, 0, 0, 0, 0, 0);

	    ncr810ThreadComplete (pThread);
	    break;

	case NCR810_SELECTED:
	case NCR810_RESELECTED:
    	    SCSI_DEBUG_MSG ("ncr810InitEvent: thread 0x%08x: (re)selection.\n",
		    	    (int) pThread, 0, 0, 0, 0, 0);
	    ncr810ThreadDefer (pThread);
	    break;

    	case NCR810_MESSAGE_OUT_SENT:
	    (void) scsiMsgOutComplete (pScsiCtrl, pScsiThread);
	    break;
	    
	case NCR810_MESSAGE_IN_RECVD:
	    (void) scsiMsgInComplete (pScsiCtrl, pScsiThread);
	    break;
	    
	case NCR810_NO_MSG_OUT:
	    /*
	     *	The target has requested a message out when there is none
	     *	pending.  Set up a NO-OP message to be sent when thread is
	     *  resumed.
	     *
	     *	The script could handle this on its own, but arguably the
	     *	host should be involved as it may represent an error.
	     */
	    pScsiCtrl->msgOutBuf[0] = SCSI_MSG_NO_OP;
	    pScsiCtrl->msgOutLength = 1;
	    pScsiCtrl->msgOutState  = SCSI_MSG_OUT_NONE;    /* sic */
	    break;
	    
	case NCR810_EXT_MESSAGE_SIZE:
	    /*
	     *  The SIOP has just read the length byte for an extended
	     *  message in.  The shared memory area is updated with the
	     *	appropriate length just before the thread is resumed (see
	     *	"ncr810ThreadUpdate()".
	     */
	    break;
	    
	case NCR810_PHASE_MISMATCH:
	    if (ncr810PhaseMismatch (pThread,
				     pThread->nBusPhase,
				     pEvent->remCount) != OK)
		{
		ncr810ThreadFail (pThread, errno);
		}
	    break;

	case NCR810_SCSI_TIMEOUT:
	    SCSI_ERROR_MSG ("ncr810InitEvent: thread 0x%08x: select timeout.\n",
			    (int) pThread, 0, 0, 0, 0, 0);

	    ncr810ThreadFail (pThread, S_scsiLib_SELECT_TIMEOUT);
	    break;

	case NCR810_SCRIPT_ABORTED:
	    SCSI_DEBUG_MSG ("ncr810InitEvent: thread 0x%08x: aborted\n",
			    (int) pThread, 0, 0, 0, 0, 0);
	    break;
	    
	case NCR810_SCSI_BUS_RESET:
    	    SCSI_DEBUG_MSG ("ncr810InitEvent: thread 0x%08x: bus reset\n",
		    	    (int) pThread, 0, 0, 0, 0, 0);
	    /*
	     *	Do not try to resume this thread.  SCSI mgr will tidy up.
	     */
	    ncr810ThreadStateSet (pThread, SCSI_THREAD_INACTIVE);
	    break;

	case NCR810_UNEXPECTED_DISCON:
	    /* not really unexpected after an abort message ... */
    	    SCSI_ERROR_MSG ("ncr810InitEvent: thread 0x%08x: "
		    	    "unexpected disconnection\n",
		    	    (int) pThread, 0, 0, 0, 0, 0);

	    ncr810ThreadFail (pThread, S_scsiLib_DISCONNECTED);
	    break;
	    
	case NCR810_ILLEGAL_PHASE:
	    SCSI_ERROR_MSG ("ncr810InitEvent: thread 0x%08x: "
			    "illegal phase requested.\n",
			    (int) pThread, 0, 0, 0, 0, 0);

	    ncr810ThreadFail (pThread, S_scsiLib_INVALID_PHASE);
	    break;

	default:
	    logMsg ("ncr810InitEvent: invalid event type (%d)\n",
		    pScsiEvent->type, 0, 0, 0, 0, 0);
	    break;
	}
    }

    
/*******************************************************************************
*
* ncr810InitIdentEvent - NCR 53C810 identification thread event processing 
*
* Parse the event type and handle it accordingly.  This may result in state
* changes for the thread, state variables being updated, etc.
*
* RETURNS: N/A
*
* NOMANUAL
*/
LOCAL void ncr810InitIdentEvent
    (
    NCR810_THREAD * pThread,
    NCR810_EVENT *  pEvent
    )
    {
    SCSI_EVENT *  pScsiEvent  = (SCSI_EVENT *)  pEvent;
    SCSI_THREAD * pScsiThread = (SCSI_THREAD *) pThread;
    SCSI_CTRL *   pScsiCtrl   = pScsiThread->pScsiCtrl;

    /*
     *  Update controller msg in/out state after script completes
     */
    pScsiCtrl->msgOutState = pThread->nMsgOutState;
    pScsiCtrl->msgInState  = pThread->nMsgInState;
    
    /*
     *	Parse script exit status; handle as necessary
     */
    switch (pScsiEvent->type)
	{
	case NCR810_RESELECTED:
    	    pScsiThread->nBytesIdent = pScsiEvent->nBytesIdent;

	    bcopy ((char *) pScsiCtrl->identBuf,
		   (char *) pScsiThread->identMsg,
		   pScsiThread->nBytesIdent);

	    ncr810ThreadStateSet (pThread, SCSI_THREAD_IDENT_IN);

    	    ncr810IdentInContinue (pThread);
	    break;

	case NCR810_MESSAGE_OUT_SENT:
	    /*
	     *	This will be after we have sent an "ABORT (TAG)" msg.
	     *	The target will disconnect any time; it may have already
	     *	done so, in which case we won't be able to